Will 17 in wheels improve ride quality?

No, ride will be bumpier, or even worse. Handling may improve a bit.

 

There's a set of TSS wheels in the private sales area now for $700. Hell of a deal.

The ride and mpg will be worse than the stock 15s. I have the 2010 Prius Five, the wheels are the same as the Persona wheels.

 

Yeah....17's have more unsprung mass or weight.

 

Any time you decrease the sidewall height of your rubber by going with a larger rim will mean there is less "cushion" to buffer your car from road imperfections. I currently have 17 inch prius plus rims and the ride is noisy, and borderline comfortable. I've bought some decent coilovers for my car and now I am debating whether I should even lower it or not considering the already jarring ride.

Not getting to you avoid a wheel upgrade tho! Just saying there are always tradeoffs. If I had a prius with 15's and was considering 17's, I'd definitely do the upgrade making sure to stay with lightweight 17x7 wheels and LRR tires.

 

Why do you think 17" rims are an upgrade?

 

The difference is when the 17s a&e included the suspension is usually more handling oriented for lack of a better word. I say this because I went from a Prius 2 (2011) to a Prius persona (2013) and the feel is more defined. Definitely not because of the 17s, thos only kick in when you need the turn traction. It does give you that, though.

 

I went with the 17" Toyota five spoke wheels the first week I had my 2012 Prius Plug In. Biggest improvement is appearance. The 15" factory wheels are too small in relation to the size of the Prius. I drive my Prius for fuel economy and I can't answer the question regarding handling. I don't have a issue with road noise or ride quality. Those that do, have more problems with poorly maintain roads. Mileage hit? Possibly, but not an issue on a Prius for me. The Toyota web site shows the SAME estimated mileage for the Prius models 1,2,3,4, (15" wheels) and the Prius 5 with the 17" wheels.

...or even worse than what?

Worse, or less. You have the 17" wheels and that gives you some credibility.

What are you road conditions in your area? Can't imagine a slight change in tire sidewall height could result in such a significant change in noise and comfort levels on good roads. Again, I give you credit for actually having 17" wheels.

Appearance.

Too much negative hype regarding 17" wheels, especially from those with no experience. My attention to detail and awareness is fairly acute. From 18 months experience, I don't see any negative issues with 17" wheels on the Prius. Tesla offers 20" wheels as a option, as well as Cadillac on their ELR. The only positive thing I can say about keeping your 15" factory wheels, they'll cost you nothing additional.

 

I was thinking from 17s to 16s just for winter purposes. The 17s are great for grip and appearance. I want to have spare 16s or even the stock 15s for the winter, since we have potholes issues in DC\VA\MD area.

 

The walls aren't thinner, the rubber isn't thinner, there's less rubber in the height of the tire, think of it as a cushion of air, there's less air for the car to ride on, which is exactly what it's doing.
The 17's have less wiggle room, less sidewall to flex and so they give a harsher ride, and they are an inch or so wider in tread, so they get less mpg's, air friction and road friction, your 15's will give the best ride and the best mpg's just get better rubber.

 

Overall tyre diameter must stay about the same to fit. So...

A larger diameter rim will require a tyre with a smaller sidewall. In general a smaller or shorter sidewall will be stiffer resulting in less cushioning which means a rougher/noisier ride. It will also result in less side to side flex which means better handling. It will not result in a larger contact patch unless the tyre is wider. In general, the shorter sidewall with less flex will allow a wider tyre because there are smaller forces trying to bend the tread off the road in cornering (they are controlled by the shorter and therefore stiffer sidewall). So IF you have a wider tyre with the shorter sidewall, keeping the entire tread on the pavement, you will have a larger contact patch, the basically rectangular part of the tread actually in contact with the pavement. This will also help in handling prowess and will increase stopping force.

Aluminum (what -most affordable- wheels are made of) is heavier than rubber. So a larger diameter wheel will move more weight farther out on the wheel/tyre, increasing rotational momentum. This will require more energy to accelerate and will loose more energy in deceleration. It will also be heavier overall, increasing unsprung weight, which will decrease handling a bit (and will be more inclined to "hop" on bumps, exacerbating the famous Prius "brake release on bump". The extra weight is reported to be why you can't have 17" wheels on a Prius with the solar/sun roof. The car gets too heavy. Of course you -could- pay more and get very light rims, such as the "CE28 Ecodrive" model. You would still have a higher rotational momentum but the unsprung weight would be lower.

There are many who feel there is a "right size" of rim for each vehicle look. As there is no accounting for taste, I won't try to.

 

In the early days of the automobile, wooden wheels were used and tires were not much more than oversized bicycle wheels, not because they wanted to make large diameter wheels, but because rubber and tire technology was much more expensive than wood.

The development of the high wall "balloon" tire softened the rough ride over poor roads.

The current "large diameter-low profile" trend is a throwback to cruder technology just for looks.

People have always been ready to pay for looks over function and efficiency.

 

Well, with all due respect the reason I went with it is because of the lateral roll resistance on the smaller sidewalls.
The looks are a side-effect alone, for me.

 

Good decision! 15's are best for anyone who cares about comfort, fuel economy, tire cost, risk of tire damage and resistance to aquaplaning. The OEM tires however are not ideal. I upgraded to Michelin Primacy MXV4 tires after putting some miles on the OEM Bridgestone Ecopia EP20 tires (quieter, more comfortable, better handling, more damage resistant and more secure on wet roads )

 

"Can't imagine a slight change in tire sidewall height could result in such a significant change in noise and comfort levels on good roads.

From 15" to 17" rim, the change in the tire sidewall height is 1" i.e. about 30% reduction.
For the part that actually flexes significantly, the reduction is probably about 35%.
A thinner cushion cannot absorb larger bumps the same way. If all other things are equal, comfort is less.

 

Our OEM are the 17" 5 spokes, with Michelin Pilot HX MXM4 215/45R17. In winter I switch to 195/65R15 Michelin X-Ice2 on Corolla steel rims. In straight smooth roads I'd be hard pressed to tell which is which. Going over speed bumps though, the X-Ice2 are much smoother. Taking a tight turn with the Pilot's I'd say it feels a bit more in control. Nothing night-and-day though.

 

I just traded in my 2012 Prius three for a 2012 Prius level five with of course with 17"wheels. I drove my three 25000 miles in the year I owned it. I installed Michelin Energy Saver AS a week after I bought it and they worked out fantasticly for me. I ran 42 in the front and 40 in the rear. Mileage and wear were great. When I drove my five with the 17"wheels with new Continental Pure Contract eco plus tires on it I thought I was driving a luxury car. The ride is super quiet, smooth and handles like a dream. I thought from reading all the info here it was really going to be a rough ride with the 17's. It was the opposite for me. I'm riding at 33 front and 32 in the rear. For me the smooth ride makes up for any loss of mpg.Maybe it will get rougher add time goes on but more it rides really smooth.

 

Correct me if I'm wrong, but you have a 9lb and 8lb difference in air pressure. Couldn't that account for some of the ride quality?

 

One other factor: the Prius that come stock with 17" have a smaller steering wheel lock-to-lock value.